Type carrier for high speed printer



Oct. 5, 1965 A. c. COOPER, JR., ETAL 3,209,682

TYPE CARRIER FOR HIGH SPEED PRINTER 5 Sheets-Sheet 1 Filed Aug. 30, 1962 S w w ARTHUR c. COOPER JR. ALBERT A. DOWD A M ATTORNEY Oct. 5, 1965 A. c. COOPER, JR., ETAL 3,209,682

TYPE CARRIER FOR HIGH SPEED PRINTER Filed Aug. 30, 1962 3 Sheets-Sheet 2 Oct. 5, 1965 A. c. COOPER, JR., ETAL 3,209,682

TYPE CARRIER FOR HIGH SPEED PRINTER 3 Sheets-Sheet 5 Filed Aug. 30, 1962 United States Patent TYPE CARRIER FOR HIGH SPEED PRINTER Arthur C. Cooper, Jr., Apalachin, and Albert A. Dowd,

Vestal, N.Y., assignors to International Business Machines Corporation, New York, N.Y., a corporation of New York Filed Aug. 30, 1962, Ser. No. 220,396 14 Claims. (Cl. 101-409) The present invention relates to printing and more particularly to a type carrier device for a high speed printer apparatus.

High speed printers are known in which a horizontal type carrier transports a plurality of uniformly horizontally spaced displaceable type elements in a reciprocating movement along a print line. The reciprocation may be incremental or it may be sweeping. Printing occurs when hammer means located at various print positions along the path of travel strike individual select type elements causing them to be displaced transverse to the direction of motion of the carrier. A resilient bias restores the displaced type elements after impact with a print medium to the normal aligned position. Upon the completion of a complete sweep of the type carrier along the print line, each of the type elements will have been presented at every print position and a complete line of data will have been printed. On the return movement of the type carrier, a second line of data may be printed.

One form of type carrier for a reciprocating printer comprises a flexible sheet metal comb. Characters are formed on the face of each of the fingers of the comb proximate the distal ends thereof. Each of the fingers of the comb is individually displaceable by hammers which strike the fingers causing them to bend out of the plane of the comb into contact with a print medium. Restoration of the bent fingers occurs through the inherent resiliency thereof.

One of the problems associated with reciprocating type carriers having displaceable type elements thereon and particularly with such type carriers having a comb-like construction, is to maintain accurate horizontal spacing and planar alignment of the type elements. Comb-like type carriers, due to their inherent flexibility, tend to bend under forces used to produce reciprocation thereby disturbing the alignment. With such misalignments, print quality, of course, suffers and damage to the type carrier can occur quite readily. In addition, comb-like type carriers heretofore have been costly to manufacture and excess wear and damage to the fingers necessitated replacement of the entire comb.

It is the general object of this invention to provide an improved type carrier particularly for a reciprocating high speed printer which overcomes the above difliculties.

It is a specific object of the present invention to provide an improved low mass type carrier for a high speed reciprocating printer having flexible type elements in which accurate alignment of type is obtainable and maintainable.

It is a further specific object of this invention to provide an improved low mass type carrier for a reciprocating high speed printer having flexible type elements in which replacement of worn and damaged type elements can be made without scrapping the entire carrier.

It is a still further object of this invention to provide an improved low mass type carrier having flexible type elements in which replacement of individual type elements can be made easily and quickly without the use of special tools, Without removal of other type elements or disassembly of the type carrier and without sacrificing accuracy in alignment.

It is a further object of the present invention to provide a low mass type carrier for a high speed reciprocating 3,209,682 Patented Oct. 5, 1965 printer which is simple in construction, economical to manufacture and maintain, and which is capable of printing at high speeds with good print quality.

It is a still further object of the present invention to provide a low mass type carrier for a high speed reciprocating printer in which malfunctioning of the printer apparatus which causes jamming of the type carrier device does not result in the destruction of the type carrier, the type elements, or coacting parts of the printer apparatus.

The above-mentioned defects of the prior art type carriers are avoided and the above objects as well as other objects are attained in accordance with the practice of the present invention by providing a type carrier comprising a rigid, light-weight support member to which one or more flexible type elements of the spring leaf type are removably attachable. Type element retaining means is provided which is also removably attachable to the type support member and which releasably engages the type elements.

In the preferred embodiment of the invention, the type support member is a thin-walled, rigid, hollow, cylindrical tube. The print elements are comb-like members having one or more flexible finger portions extending from a common base portion and having characters formed proximate the distal ends thereof. The base portion of each of the type elements includes an extension portion adapted to be mounted onto the tube support and to coact therewith and the retaining means to form a type carrier device. For mounting the type elements, the tube support is provided with passageways into which the extension portion of the type elements extend. The retaining means preferably take the form of spring clips which are adapted to be spring attachable to the tube and which releasably engage the extension of the type elements within the passageways of the tube support.

Further in accordance with the present invention, passageways are formed in the tube support by two sets of openings through the wall of the tube support. The first set of openings comprises a plurality of slits linearly aligned and uniformly spaced apart in an axial manner. The second set of mounting openings comprises a plurality of uniformly spaced slits formed through the wall of the tube support in radial alignment with related slits of the first set. In addition, each of the openings of the second set comprises enlarged access apertures at the ends of the slit portion to receive the spring clips. The openings of the second set are, like the openings of the first set, separated by interopening wall portions between adjacent access apertures. 1

In the preferred embodiment, the spring clips are U- shaped springs having a pair of spaced resilient laterally deflectable spring fingers connected to a spring bridge member at one end thereof and having gripping means proximate the distal ends thereof. The attachment of the spring clips is obtained by a snap-on action. This preferably is provided by constructing the spring member with a pair of inwardly facing concave bends connecting the bridge member to the spring fingers. The concave bends and bridge member portions of the U-shaped clips coact to grip the tube at the interopening wall portion thereof and at the same time, the concave bends provide a fulcrum for the spring fingers which is in contact with the external surface of the interopening wall portion in the second set of slits.

For attaching the type element to the support member with a snap action, the extension is provided with hook means releasably engageable by said gripping means of the spring clip fingers. In a first embodiment, the extension, in a preferred form, is provided with hook means on both lateral edges. The leading and trailing edges of the hook are both cammed to permit manual insertion and removal of the extension from the tube passages. The trailing edge, however, is cammed more abruptly so that a firmer retention of type element is provided and greater force is required to effect removal. In addition, the hook means are laterally oppositely faced and engage spring fingers of separate adjacent spring clips. When a type element is mounted by inserting the extension of the base portion thereof into related radially aligned slits, the lateral edges of the type element extension deflect the spring fingers of the spring clips inwardly. Because of the concave bends in the spring fingers, they bend about an external fulcrum so that the spring clips grip the wall of the tube when the type element is being mounted on the tube as well as when it is being removed.

Thus it will be appreciated that assembly of type elements can be achieved with ease and without use of special tools. In addition, the construction provides a light-weight, low mass type carrier having good alignment of type.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.

In the drawings:

FIG. 1 is a perspective view schematically showing a printer apparatus in which a type carrier device of the present invention has utility.

FIG. 2 is an elevation view in schematic showing a hammer construction and drive mechanism useful in the printer apparatus of FIG. 1.

FIG. 3 is an isometric view in partially exploded form showing the type carrier of the present invention with portions in phantom.

FIG. 4 is a front elevation of the type carrier of FIG. 3 showing the sequence of assembling the type elements to the tubular type support member with portions of the tube shown in cross section.

FIGS. Sa-Sc show in sequence the coaction of the parts upon removal of the type elements from the type support member in the type carrier device of FIG. 3 with parts shown in cross section.

FIG. 6 is a front elevation view in partial cross section showing a second embodiment of the type carrier device of the present invention.

FIGS. 7a and 7b are front elevation views in partial cross section showing a further embodiment of the type carrier device of the present invention.

FIG. 8 is a front view of the spring element portion of the type carrier device in its various embodiments.

Referring to the drawings:

FIG. 1 shows .a printer apparatus which includes a platen 10, a print medium 11, and an ink ribbon 12 extending across the print medium 11 from supply and takeup reels 13 and 14. The feeding of the paper 11 and ink ribbon 12 may be performed by suitable means in any well known manner and in particular may include electrical or mechanical means for advancing the paper a line at a time. A plurality of uniformly spaced hammers 15 are arranged in a linear array along a print line, one hammer being located at each print position. While various forms of hammers may be used and various assemblies and operators employed to obtain operation of the hammers at the various print positions, the preferred print hammer mechanism takes the form described in US. patent application of Roland D. Nelson and Donald K. Rex, Serial No. 113,201 filed May 29, 1961. As shown briefly in FIGS. 1 and 2, in the hammer apparatus of the aforesaid application, each hammer 15 comprises a body portion 16 having a slot 17 and all of the hammers 15 are pivotally mounted on a common stationary support rod 18. The hammer mechanisms 15 further include a striking arm 19 extending outwardly from the central body portion 16 and a firing arm 20 extending below body portion 16 and to the rear thereof.

Referring further to FIGS. 1 and 2, each hammer 15 in the preferred version of a hammer operator mechanism is provided with an individual holding magnet 21 having suitable energizing means, such as winding 22. A return spring 23 is attached at one end to a stationary support 24 and has its free end in biasing contact with the body portion 16 at the edge surface above the pivot rod 18.

The hammer firing mechanism of the aforesaid application includes a cantilever leaf spring 25 for each hammer, each spring being mounted on a bail 26 which is pivotally suspended from a shaft 27 on one or more spaced apart arms 28. Each spring drive 25 is made up of a number of leaves 29 through 32 of progresssively decreasing lengths. Leaf 30 is provided with an angularly protruding finger 33 at its distal end. The drive mechanism includes a spring reset assembly made up of a spring stop bail 34 pivotally mounted on shaft 27 by means of arm 35. Each hammer firing mechanism is operated by a pair of cams 36 and 37 which are keyed in appropriate manner to rotatable shaft 38. Cam follower 39 is carried by arms 28 in position to bear against cam 36 while cam follower 40 is carried by arm 35 in position to bear against cam 37. Cam followers 39 and 40 are kept in contact with their respective cams through the reaction of spring 41. While FIG. 2 shows a hammer firing mechanism for a single hammer 15, it is, of course, understood that the same firing mechanism would be supplied for each of the hammers 15 of the printer apparatus of FIG. 1. For this purpose, the various shafts '27 and 38 may be mounted to a common support frame which supports the hammer mechanisms 15, the platen and the return spring 23 of the printer apparatus of FIG. 1.

Positioned between the print hammers 15 and the type ribbon 12 is a type carrier device comprising a plurality of spring leaf type elements 50 removably mounted on a horizontal reciprocating type element support tube 51. Each of the type elements 50 includes a mounting extension portion 52 and a plurality of coplanar integral finger extensions 53 having type characters (not shown) formed on the distal ends thereof.

In the line printer apparatus of FIG. 1, each type hearing finger 53 of type element 50 is provided with a different type character and each type element 50 has plural type characters forming a portion or segment of a type alphabet. In accordance with this invention, a complete type alphabet is provided for printing by assembling plural type elements 50, i.e., segments, in releasable manner on support tube 51 so that each type segment 50 is individually removable and replaceable in the assembly. To print the various characters to form a complete line of print on paper 11, type elements 50 are moved horizontally past the array of hammers 15 and the various hammers are selectively operated to strike appropriate type characters at predetermined positions under control of means which might include memory devices or the like not shown.

The operation of the firing mechanism for causing the hammers 15 to strike the type bearing fingers 53 of type element 50 is described briefly as follows: The rotation of shaft 38 causes cams 36 and 37 to assume a position which causes follower 40 to drop arm 35 causing bail 34 to assume a dropped position such that spring 29 is extending beyond the edge of bail 34. At the same time, cam follower 39 riding on cam 36 will have dropped spring bail 26 so that spring leaf 29 is to the right of the extension 20 of hammer 15. As shaft 38 continues to rotate, cam follower 39 raises arms 28 and bail 26 upwardly so that spring 29 engages the right side of extension 20 of hammer .15. With winding 22 of holding magnet 21 energized, hammer 15 is subjected to a clockwise force caused by the deflection of spring 29 as it is brought to bear on extension 20 through the rotation of the cams by shaft 38. When a type finger 53 has been positioned at the appropriate position in front of hammer 15, the current in coil 22 may be switched off and the control magnet 21 releases hammer 15. Due to the force applied to extension 20 by spring 29, hammer 15 pivots about shaft 18. As the hammer pivots, the tip of the drive spring 29 slides off the lower tip of the firing arm 20 as shown in FIG. 2 and comes to rest against the spring stop bail 34. The acceleration given to the hammer 15 causes it to continue in its clockwise movement until it strikes the type finger 53 and forces the type against the ink ribbon 12, the print medium 11, and the platen 10. Hammer 15 then rebounds away from platen in a counterclockwise direction toward the holding magnet 21. The hammer return spring 23 hearing against the upward extending flange of body portion 16 acts against finger 33 to hold the hammer after rebound in position slightly spaced from the edges of the magnets 21. Further details of operation of the hammer firing mechanism as well as information on the repetitive selective firing of the hammers 15 as various type fingers 53 are moved into position may be more fully understood by referring to the description in the aforesaid application of Roland D. Nelson and Donald K. Rex.

The horizontal motion of the type carrier which brings the various type fingers 53 into the various print positions may be provided by a rack and pinion gear arrangement which includes a pinion gear 54 connected in a suitable manner to any Well known reversible drive member (not shown) and a rack gear 55 which is attached to the underside proximate one end of tube 51. A flag member 56 attached to the upper side of tube member 51 moves through a detector means 57 which through suitable control means connected to the pinion gear drive limits the stroke of tube 51 and reverses its direction.

Printing by operation of the hammers 15 to strike the type fingers 53 of type element 50 may be performed at rest or on-the-fly. In the former case, the type carriers 50 move into position so that each type finger is aligned with a different hammer 15 and stopped. Hammer 15 is fired, then the type carrier moves the type elements 50 to the next horizontal position aligning each of the type fingers 53 at the next adjacent hammer position. The process is repeated for the full length of the print line. When printing occurs on-the-fiy, the tube member 51 is moved without intermediate interruption across the entire length of stroke parallel to the print medium 11. In either case, when hammers 15 strike the type fingers 53, the same bending action of the fingers 53 causes them to be displaced from the plane of the type elements 50. In accomplishing such deflection, the hammer means 15 enters the confines of the type element 50. It will be readily apparent that to accomplish the successive steplike movement or the continuous sweeping movement of the type elements 50 past the hammer mechanisms at high speeds that a failure on the part of the hammer mechanism 15 to be retracted might cause some difficulty which would tend to damage the print mechanism. In addition, it will be readily appreciated that extensive operation of the printer apparatus in the manner just described causes wear and other mechanical problems which may require the replacement of the type elements 50 from time to time.

In a first embodiment of a type carrier device in accordance with the present invention, as shown in FIGS. 3-5, each of the type elements or segments 50 is a spring leaf member having a base portion 52 from which a plurality of integral deflectable type fingers 53 extend in a common plane with each other and base portion 52. The base portion 52 in the first embodiment comprises a single mounting extension 54 between a pair of horizontal positioning shoulders 55 and 56. Immediately below shoulders 55 and 56 on extension 54 are a pair of vertical positioning shoulders 57 and 58 formed in the lateral edges of extension 54. Cuts 59 are formed in the corners of the edges of base portion 52 where horizontal shoulders 55 and 56 meet vertical shoulders 57 and 58 to simplify the manufacturing procedure by eliminating the need for making shoulders meet at a precise sharp corner. In addition, cuts 59 would afford some measure of stress relief.

Below shoulders 57 and 58 extension 54 is provided with a pair of oppositely facing lateral retaining hook means 61 and 62 formed 'by notches 63 and 64 in the lateral edges of extension 54. The leading edges 65 and 66 of retaining hooks 61 and 62, respectively, are downwardly laterally cammed from the point of hooks 61 and 62 and the trailing edges 67 and 68 are upwardly laterally cammed therefrom so that both pairs of camming edges of the respective hooks are oppositely directed. The camming of leading edges 65 and 66 is more pronounced while the camming of trailing edges 67 and 68 is more abrupt.

In the preferred embodiment, the support for type elements 50 comprises a rigid, thin-walled, hollow tube 51. For mounting the type elements 50 thereon, tube 51, which is preferably formed of a light-weight material such as aluminum or the like, is provided with passages adapted to receive extensions 54. In the preferred form, the passages are formed by an upper and lower set of slits 70 and 71, respectively, radially aligned with each other. Each of the slits 70 in the upper set is preferably a rectangular opening adapted to expose straight edges of the wall of tube 51 for engagement with the sides of extension 54. Each of the slits 71 in the lower set preferably has straight edges and in the embodiment of FIGS. 3-5 terminates at opposite ends in enlarged rectangular access apertures 72. Axial coplanar alignment of type elements 50 is obtained by a linear axial alignment of slits 70 and 71 in each set and by a radial alignment of each slit 70 with a corresponding slit 71 and related access apertures '72. The slits 70 of the upper set are spaced apart in a horizontal direction so as to be separated by interopening wall portions 73 While similar wall portion 74 separates access apertures 72 of adjacent slits 71. To obtain uniformity of spacing of the type fingers 53, each of the slits 70 and 71 is uniformly axially spaced along tube 51 and each type element as well as the type fingers 53 are the same size.

In accordance with this invention, type elements 50 are mountable on and removable from the tube support member in a manual operation which requires no special tools. Mounting of the type elements 50 on tube 51, of course, occurs by inserting extension 54 of type element 50 through upper and lower related slits 70 and 71. When inserted, type elements 50 are retained on tube 51 in such a manner that they are removable as Well as mountable by a manually applied force. For this purpose, a plurality of spring retaining elements 75 are provided which are attachable to tube 51 in such a manner that they releasably engage extensions 54 of the type elements 50 through cooperation with the hooks 61 and 62 thereof. In addition, the spring retaining elements 75 are constructed so as to be individually removably mountable in a simple manual operation but will not be removable by the operation of mounting the type segments 50 onto tube 51.

In the preferred form, each spring retaining element is designed from a single piece of spring steel or the like formed to have a generally U-shaped configuration. Referring to FIG. 8, each of the spring elements 75 comprises a bridge portion 76 connecting a pair of integral upwardly extending spaced apart gripping fingers 77 and 78. Each of the gripping fingers 77 and 78 is provided with a series of successive bends designed to form a tube gripping portion in combination with the bridge portion 76 and type element gripping means adapted to engage the hooks of type elements 50. More specifically, gripping finger 77 beginning at the point of its connection to the right end of bridge portion 76 is provided with an inwardly facing concave bend 80 which leads to an inwardly convex bend 81. Extending beyond bend 81, spring finger 77 is further shaped to terminate with an outwardly convex bend 82.

Similarly, the second or left spring finger 78 of spring element 75 beginning at the left terminus of bridge portion 76 has an inwardly facing concave bend 83 leading to an inwardly convex bend 84 and, extending further, is shaped to terminate in an outwardly convex bend 85. It is to be noted in connection with the tube gripping portion of spring element 75 that the corresponding bends 80 and 83 at the point where they depart from bridge 73 bend downwardly in a curvilinear manner then reverse direction to extend upwardly.

In the construction shown in FIG. 8, the inner surfaces of spring fingers 77 and 78 proximate bends 80, 81 and 83, 84 form a tube gripping portion adapted to engage the wall of tube 51 while the outer surfaces of spring fingers 77 and 78 along bends 82 and 85 are operable for engaging the camming edges of extension 54 which form the hook elements 61 and 62 of type elements 50.

In the assembly of the type carrier device of the present invention, the spring elements 75 are attached to tube 51 as follows. Gripping fingers 77 and 78 are inserted through adjacent access apertures 72 on opposite sides of interopening wall portions 74 to bring the inner surfaces of convex bends 81 and 84 into contact with the edges of wall portions 74. The spring element 75 is attached to the tube 51 by applying a radially inward pressure to bridge portion 76. This causes bends 81 and 84 to cam the spring fingers 77 and 78 so as to deflect them laterally. As the high points of bends 81 and 84 of the spring fingers 77 and 78 pass over the edge of the tube wall, the energy stored in the deflected fingers is released causing spring 75 to be drawn inwardly into position with a snap action. Additional spring clips 75 are likewise attached to each of the separated wall portions 74 at the various positions along the tube 51. When thus attached, spring clip 75 grips the wall of tube 51 by coaction of bridge 76 and spring fingers 77, 78. When thus attached, bridge 76 is in contact with the external surface of wall portion 74. By virtue of the bends 80 and 83, the spring fingers 77 and 78 extend around the edges of wall portion 74 embracing tube 51. By such construction, spring fingers 77 and 78 are deflectable about a fulcrum which is external to tube 51. Thus each spring finger 77, 78 is virtually independently deflectable. In other words, spring finger 77 is deflectable upon the insertion and removing of type elements from the passageway occupied by spring finger 77 without materially effecting the gripping action of spring finger 78 in an adjacent passageway for an adjacent type element 50 and vice-versa. In the arrangement just described, spring fingers 77 and 78 occupy positions in adjacent passages and each passage is occupied by two spring fingers each from a different spring clip 75. In such an arrangement, type elements are maintainable in firm attachment with good alignment on tube 51 even though an individual spring clip may become worn or damaged through extensive use.

The mounting of type elements 50 on tube 51 and the coaction of tube type elements and spring retaining means is more clearly understood by reference to FIG. 4. As seen in that figure, the assembly of type elements 50 occurs by manually inserting the bottom edge of extension 54 in one of the upper slits 70. As the extension 54 penetrates the passageway formed by a pair of related upper and lower slits 70 and 71, respectively, the leading camming edges 65 and 66 of hooks 61 and 62 engage the convex surfaces 82 and 85 of type gripping fingers 77 and 78 of adjacent spring retaining element 75. Continued pressure on type element 50 causes extension 54 to advance radially downward through tube 51 so that cam edges 65 and 66 deflect the spring fingers until they pass over the high point of hooks 61 and 62. When the high points of bends 82 and 85 pass over the high points of hooks 61 and 62, the surfaces of bends 82 and 85 of adjacent clips come in contact with the trailing camming edges 67 and 68 of hooks 61 and 62. Due to the energy stored in deflecting the spring fingers 77 and 78, a downwardly directed force is applied to the trailing camming edges 67 and 68 causing the type element 50 to move downwardly into tube 51. At the time the downward force is applied to the trailing edges 67 and 68, extension 54 will have penetrated through slit 71 and its associated apertures 72. With the extension 54 extending through the radially aligned slits 70 and 71, the downward force applied by the deflected spring fingers 77 and 78 causes the type element to move downwardly with a snap action which causes the horizontal shoulders 55 and 56 of base portion 52 to come to rest against the upper surface of interopening wall portions 73. At the same time, vertical shoulders 57 and 58 will have entered slit 70 and come in contact with the side edges of the wall portion 73 of tube 51. Thus type element 50 is held firmly and squarely on tube 51 and is accurately aligned and positioned but is relatively easily removable by application of a radially upward force applied manually.

The removal of type element 50 is illustrated in connection with FIGS. Sa-Sc which show the sequence of actions occurring when a type element 50 becomes jammed and tube 51 continues its horizontal motion. For purposes of illustration, the direction of motion of tube 51 will be assumed to be to the left in FIGS. Sa-Sc as indicated by arrow 60. A counterforce to the right is applied to the type element 50 at a point above the tube 51. Such a counterforce represented by arrow 60a will produce a moment on type element 50 causing it to turn about the lateral edge of horizontal shoulder 56. The turning moment causes type element 50 to move upwardly with extension 54 withdrawing from lower slit 71. Camming edge 67 of hook 62 will deflect spring finger 78 of one clip 75 and camming edge 68 will deflect the spring finger 77 of the second adjacent clip 75. The turning of type element 50 about the fulcrum provided by shoulder 56 as shown in FIG. 5b causes hook 61 to deflect spring finger 77 to the point of release, extension 54 is almost totally withdrawn from slit 71 and apertures 72 and hook 62 further deflects spring finger 78 of adjacent clip 75. In FIG. 50 type element 50 has turned about shoulder 56 to the point where extension 54 is clear of slit 71 and apertures 72 with hook 61 clear of slit 70. Hook 62 due to action of camming edge 68 has been released by deflected spring finger 78. Spring fingers 77 and 78 of the adjacent clips snap back to normal position on opposite ends of the passageway formed by the related slits 70 and 71.

In the embodiment of FIG. 6, type element 50 has a bifurcated base portion 54 thereby providing a pair of spaced mounted extensions 80 and 81. To accommodate the extensions 80 and 81, tube 51 is formed to have a passageway for each extension. As in the embodiment of FIGS. 3-5, the passageways are formed by an upper and lower set of radially aligned slits 70 and 71, respectively, the slits 71 in the lower set terminating at one end in access apertures 72. Spring clips 75 are attached to interwall portions 74 between a pair of slits 71 of the lower set in the same manner as in FIGS. 3-5. Interwall portions 73 in tube 51 between slits 70 coact with outer horizontal shoulders 55 and 56 and intermediate extension shoulder 82 of base portion 52 of type element 50. In the embodiment of FIG. 6 each of the extensions 80 and 81 is also provided on the external edges with vertical tube engaging type element positioning shoulders 57 and 58 and internal edge vertical positioning shoulders 83 and 84. By providing vertical tube engaging shoulders 57, 58 and 83, 84 on both sides of extensions 80 and 81, positioning of type element 50 on tube 51 can be even more accurately controlled. Cuts 59 are provided between the vertical and horizontal shoulders.

In the embodiment of FIG. 6 the type element extensions 80 and 81 are releasably engaged by both spring fingers 77 and 78 of a single spring element 75. For that purpose, then, the inner edges of .the extensions 80 and 81 are formed with retaining hooks 85 and 86. The hooks 85 and 86 are provided with leading camming edges 87 and 88 and trailing camming edges 89 and 90. As in the embodiment of FIGS. 3-5, the trailing edges 89 and 90 are more abrupt so that the force for removal of type element 50 is required to be greater than the force for insertion. As shown in FIG. 6, the retaining hooks 85 and 86 of extensions 80 and 81 are inwardly facing and both the leading and trailing camming edges are inwardly directed. Thus when insertion and removal is performed, both spring fingers 77 and 78 of the same spring element 75 are inwardly deflected. Of course, such deflection produces a double lock-ing action around tube wall portion 74 which maintains spring 75 more firmly attached to the wall portion 74 of tube 51 during the insertion as well as the removal of type element 50 from tube 51.

In the embodiment of FIGS. 7a and 7b, the base portion is bifurcated in the manner of FIG. 6, but the mounting extensions are provided with double acting retaining hooks. In addition to internal hooks 85 and 86, mounting extensions 80 and 81- are respectively provided with laterally exterior retaining hooks 91 and 92. The leading and trailing external edges 93, 94, 95 and 96 of the hooks 91 and 92 are cammed in a symmetrical manner with corresponding inward leading and trailing camming edges 87 and 88. To accommodate the new retaining hooks, the lower slits 71 in tube 51 terminate both ends in access apertures 72 so that spring clips 75 are attachable to the wall portions 74 between each passageway. With such an arrangement, each type element 50 is retained by three separate spring clips 75 so that accuracy of alignment, fixity of positioning, and reliability of attachment are assured to an even greater degree. Thus, if one of the spring fingers of clip 75 or both spring fingers should fail to maintain the engagement with type element 50, an adequate release attachment is maintained by the coacting spring fingers of adjacent spring clips 75.

While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. A type carrier device comprising in combination (a) a rigid type element support member,

(b) a plurality of type segments individually mountable on said support member,

(c) said type segments having a base portion mountable on said support member and a plurality of resilient type fingers extending therefrom, and

(d) means for releasably maintaining said individual type segments in fixed array on said support member including (e) spring clip means having a first gripping portion for releasably attaching said spring clip means to said support member,

(f) said spring clip means having a second gripping portion for releasably gripping the base portion of said type segments for retaining said type segments on said support member,

-( g) said second gripping portion being operatively connected with said first gripping portion whereby the engagement of said second gripping portion by the base portion of said type segments produces a locking action of said first gripping portion to said support member.

2. A type carrier device comprising in combination (a) a rigid type element support member having type element receiving passages therein,

(b) a plurality of spring leaf type elements having base portions insertable within said passages and integral spring type fingers extending from said base portions, and

(c) means for releasably retaining said type elements on said support member with said type fingers of said plural type elements in an aligned array including (d) spring clip means having a first gripping portion for releasably attaching said clip means to said support member,

(e) said spring clip means having a second gripping portion for releasably gripping the base portion of said type elements for retaining said type elements on said support member,

(f) said second portion being within said passages on attachment of said first gripping portion to said support member,

(g) said second gripping portion being operatively connected with said first gripping portion whereby insertion and removal of said base portion of said type elements within said passages into engagement with said second gripping portion produces a locking action of said first portion to said support member.

3. A type carrier device in accordance with claim 2 in which (a) said type element support member is a cylindrical, hollow tube and said passages are formed by aligned openings in the Walls of said tube,

(b) said first gripping portion of said spring clip means is removably attachable to the wall of said tube, and

(c) said second gripping portion includes resilient finger elements extendable into the central opening of said hollow tube on attachment of said first gripping portion to said tube.

'. 4. A type carrier device in accordance with claim 3 in which (a) the base portions of said type elements have hook means for deflecting said resilient finger elements of said second gripping portion for producing said locking action of said first gripping portion.

5. A type carrier device in accordance with claim 4 in which (a) said hook means of said base portions of said type elements includes (b) camming means for deflecting said resilient finger of said second gripping portion upon application of a predetermined force whereby said type elements are readily mountable and removable from said support member.

6. A type carrier device in accordance with claim 4 in which (a) said hook means of said base portions of said type elements includes (b) a first camming means on the leading edge of said hook means for deflecting said resilient fingers of said second gripping portion over said hook on insertion of said base portion into said passages in said tube member, and

(c) a second camming means on the trailing edge of said hook means for deflecting said resilient fingers over the hook on application of a predetermined force for extracting said base portion from said passages.

7. A type carrier device in accordance with claim 3 in which (a) said spring clip means comprising spring clip elements which are U-shaped spring members having a pair of spaced spring fingers connected by a bridge member,

(b) said bridge member and said spring fingers coacting to form said first gripping portion spring attachable to said wall of said tube member.

8. A type carrier device in accordance with claim 7 in which (a) said passages in said tube member are separated by interopening wall portions, and

(b) said wall gripping portion of said U-shaped spring members engages said interopening Wall portion with said bridge member along the external surface of said interopening wall portion and said spring fingers extend into adjacent passages, and

(c) each of said spring fingers is laterally defiectable by said base portion of said type element so as to perform a locking operation of said clip elements to said tube member upon insertion and removal of said base portions from said passages.

9. A type carrier device in accordance with claim 8 in which (a) said bridge member of said U-shaped spring members is connected to said spring fingers by inwardly facing concave bends spring defiectable for receiving and gripping said interopening wall portions,

(b) said bends providing a fulcrum for said spring fingers against the external surface of said interopening wall portion of said tube member.

10. A type carrier device in accordance with claim 3 in which (a) each of said base portions of said type elements has a single extension insertable within a single passage,

(b) said single extension having first and second outwardly extending lateral hook means on opposite side edges thereof,

(c) each of said hook means having lateral edges independently engageable with a resilient finger of separate adjacent spring clips insertable within said passage.

11. A type carrier device in accordance with said claim 3 in which (a) said openings in said tube member are radially aligned slits in the walls thereof, and

(b) said base portion of said spring leaf type elements includes an integral extension insertable through radially aligned slits into contact with the spaced wall edges of said tube defining said slits, whereby said tube members form a turning couple in opposition to deflection of said type fingers of said type elements.

12. A type carrier device in accordance with claim 7 in which (a) each of said base portions of said type elements is bifurcated to provide a pair of mounting extension members,

(b) said pair of extension members having inwardly facing camming edges coactable with both of said spring fingers of said U-shaped spring members.

13. A type carrier device in accordance with claim 7 in which (a) said base portion is bifurcated so as to provide a pair of mounting extensions,

(b) said mounting extensions having both internal and external lateral camming edges,

(c) said internal camming edges being coactable with a pair of spring fingers of a first U-shaped spring clip, and

(d) said external camming edges of said mounting extensions being coactable with spring fingers of adjacent spring retaining clips.

14. A type carrier device comprising in combination (a) type support tube having a plurality of apertures in the wall thereof,

(b) said apertures forming passageway means for radially extending type elements mountable on said support tube,

(c) a plurality of type elements for mounting on said support tube,

((1) said type elements having a mounting portion insertable into said apertures for engaging the aperture defining edges of the wall of said tube member and a character bearing portion extendable radially outwardly from said tube support, and

(e) means for releasably retaining said type elements in radially extending attitude on said tube member comprising (f) spring means having a fastening portion spring attachable to the wall of said tube member and a gripping portion extendable into said tube member,

(g) said gripping portion having defiectable gripping means for releasably engaging said extension portion of said type elements.

(h) said gripping portion being operatively connected to said fastening portion whereby the insertion of said type elements within said passageways causes said gripping means to be deflected for producing a locking action of said fastening portion on said tube member.

References Cited by the Examiner UNITED STATES PATENTS 713,323 11/02 Merritt 101--20 994,971 6/11 Beck 101111 X 1,138,985 5/15 Shotwell 10ll09 X 1,274,363 8/18 Allen l01-381 1,853,211 4/32 Hoffmann 10138l 2,694,975 11/54 Garver 101l09 X 2,936,704 5/60 Hense 10193 3,041,965 7/62 Sasaki 101--l11 WILLIAM B. PENN, Primary Examiner. 

1. A TYPE CARRIER DEVICE COMPRISING IN COMBINATION (A) A RIGID TYPE ELEMENT SUPPORT MEMBER, (B) A PLURALITY OF TYPE SEGMENTS INDIVIDUALLY MOUNTABLE ON SAID SUPPORT MEMBER, (C) SAID TYPE SEGMENTS HAVING A BASE PORTION MOUNTABLE ON SAID SUPPOORT MEMBER AND A PLURALITY OF RESILIENT TYPE FINGERS EXTENDING THEREFROM, SAND (D) MEANS FOR RELEASABLY MAINTAINING SAID INDIVIDUAL TYPE SEGMENTS IN FIXED ARRAY ON SAID SUPPORT MEMBER INCLUDING (E) SPRING CLIP MEANS HAVING A FIRST GRIPPING PORTION FOR RELEASABLY ATTACHING SAID SPRING CLIP MEANS TO SAID SUPPORT MEMBER, (F) SAID SPRING CLIP MEANS HAVINGA SECOND GRIPPING PORTION FOR RELEASABLY GRIPPING THE BASE PORTION OF SAID TYPE SEGMENTS FOR RETAINING SAID TYPE SEGMENTS ON SAID SUPPORT MEMBER, (G) SAID SECOND GRIPPING PORTION BEING OPERATIVELY CONNECTED WITH SAID FIRST GRIPPING PORTION WHEREBY THE ENGAGEMENT OF SAID SECOND GRIPPING PORTION BY THE BASE PORTION OF SAID TYPE SEGMENTS PRODUCES A LOCKING ACTION OF SAID FIRST GRIPPING PORTION TO SAID SUPPORT MEMBER. 